March 24, 2025 Story by: Editor
Research from Rutgers Health highlights the need for caution when interpreting blood tests for Alzheimer’s disease—particularly for Black patients.
“These tests are primarily designed for primary care physicians and older adults concerned about cognitive health,” said William Hu, senior author of the study published in Alzheimer’s and Dementia. Hu, who is also the director of the Rutgers Center for Healthy Aging Research and Chief of Cognitive Neurology & Alzheimer’s Disease Clinic, added, “While they may provide some value to doctors who understand their limitations, there is no reason for patients with memory concerns to purchase these tests, which cost between $1,200 and $2,000 and are rarely covered by insurance.”
The study found that concentrations of a key Alzheimer’s biomarker are significantly lower in blood than in spinal fluid, where they have been validated as a diagnostic tool—mainly in white patients. The difference is even more pronounced in Black patients, who naturally have lower biomarker levels in their spinal fluid. Compounding the issue, declining memory function can also elevate blood biomarker levels.
“The blood tests come with several caveats,” Hu noted. “Because these proteins transfer poorly from spinal fluid to blood, many patients—especially those with mild disease—will go undiagnosed. At the same time, other health conditions can increase these proteins in the blood, leading to false positives.”
Source: Rutgers Health